1. Field of the Invention
The present invention relates to a head protection airbag which is configured to be folded and stored at an upper edge of a window on the inside of a vehicle, the airbag is mounted and fixed to the body of the vehicle at the upper edge side, so that the airbag protrudes downward from where it is stored, due to an inflow of inflation gas from an inflator, deploying while inflating so as to cover the inside of the window.
2. Description of the Related Art
In general, as shown in JP-A-2008-87519, head protection airbags are formed so that, at the upper edge of a shielding main body portion covering the inside of a window when the inflation is completed, a mounting portion for mounting the airbag on the upper edge of the window or a substantially tubular connection port which is connected to an inflator and allows an inflow of inflation gas to the inside of the shielding main body portion are formed so that one protrudes from the shielding main body portion. In the conventional head protection airbags, the mounting portion or the connection port is formed integrally with the shielding main body portion by double weaving.
In general, the airbags manufactured by double weaving are formed by cutting a sheet-like airbag material in which an inflation portion which is inflated by an inflow of inflation gas between a vehicle inside-facing wall and a vehicle outside-facing wall, and a non-inflation portion which is configured to couple the vehicle inside-facing wall to the vehicle outside-facing wall but to have no inflow of inflation gas inside it are woven in a predetermined shape. Accordingly, when the mounting portion or the connection port are formed integrally with the shielding main body portion by double weaving, the upper and lower width dimensions of the airbag material necessary for the manufacturing of airbags are required to be larger by an amount equal to the protrusion of the mounting portion or the connection port. Further, in the conventional airbags, there is room for improvement from the viewpoint of enhancing the airbag material yield. This is because the mounting portion or the connection port is disposed partially along the front-back direction and the material around the mounting portion or the connection port is unused.